Adenocarcioma of rectum: T1 lesion

Case contributed by Dr Jan Frank Gerstenmaier


Rectal bleeding. Colonoscopy found tumour and polyps.

Patient Data

Age: 70-75Y
Gender: Male


Malignant appearing rectal polypoid lesion


MR Rectal Cancer Staging

MR Rectal Cancer Staging

Multiplanar noncontrast small field of view MR imaging of the pelvis has been obtained. The high re

ctal tumor lies ~ 10 cm above the anal verge and 6 cm above the anorectal junction. The superior border lies below the peritoneal reflection. It measures ~ 2

cm in

length, and extends from 4 to 7 o'clock (clockwise). Tumor does not clearly the muscularis propria

and does not extend into the mesorectal fat. The colorectal resection margin (CRM) is not at risk. There is no evidence of extramural venous invasion. The peritoneal reflection is not involved. There are no suspicious mesorectal lymph nodes. There are


pelvic side wall lymph nodes suspected of tumor involvement. There are no bone mets evident. There is no extension into the presacral fat.

Right hip subchondral cysts.

The other polyps described in the requisition are not identified with certainty on this examination.

Conclusion: This is a high

T1 (or early T2) N0 MX rectal tumor, 11.2 cm from the anal verge.

Reported by:


Staging CT

CT Chest, Abdomen and Pelvis.

Dynamically enhanced axial images have been obtained through the chest, abdomen and pelvis following intravenous and oral contrast.

Within the chest, a 5mm nodule abuts the oblique fissure in the anterior aspect of the left lower lobe. Minimal atelectasis is seen in base of the left lingula lobe.

No pleural or pericardial effusion.

No mediastinal, hilar, axillary or retrocrural lymphadenopathy.

Within the abdomen and pelvis, the liver is of mildly decreased attenuation suggesting fatty infiltration. No focal liver lesion is seen.

The spleen, pancreas and adrenal glands have normal appearance.

Small bilateral low-attenuation renal lesions have CT features consistent with cysts. The largest lies in the mid pole of the right kidney measuring approximately 15 mm, with exophytic 13 mm cyst in the inferior pole of the left kidney. No hydronephrosis.

Multiple small and borderline in size and left para-aortic lymph nodes are demonstrated. None of which however has significantly enlarged on size criteria. There is no mesenteric or inguinal lymphadenopathy. No free fluid or focal collection is seen within the abdomen or pelvis.

Colonic diverticular disease is demonstrated. No evidence of bowel obstruction. The known rectal lesion is not clearly identified. The surrounding perirectal fat is preserved.

No suspicious bony lesion.


A 5 mm left lower lobe pulmonary nodule is non-specific. Correlation, with an early followup study in 3 months time or comparison with any prior imaging is suggested.

There is no definite evidence of metastatic disease within the chest, abdomen or pelvis.



CLINICAL NOTES: 1. Rectal cancer Ultra low anterior resection 2. Distal Donut MACROSCOPIC DESCRIPTION: 1. "Rectum": A 275mm length anterior resection, diameter 20-30mm. The anterior peritoneal reflection is 30mm from distal margin. The posterior perirectal fat is non-peritonealised from 170mm from distal margin. There is up to 100mm mesocolon, up to 29mm posterior perirectal fat, up to 20mm anterior perirectal fat. Within the rectum, at the level of the anterior peritoneal reflection, (22mm from distal margin and 212mm from proximal margin), there is a pale brown smooth discoid tumor, 20x13x9mm. The tumor is causing a puckering of the underlying mucosa but appears to be limited to mucosa and submucosa, with intact muscularis propria. Tumor submitted in full. The tumor is on posterior wall of rectum, where there is up to 19mm of posterior perirectal fat (tumor is 30mm from posterior non-peritonealised surface). The distal 120mm of rectum shows diffuse polypoid lesions, 2-5mm maximum dimension (approximately 45 in total). The polyps are present at distal margin, and 155mm from proximal margin. The sigmoid mucosa contains a single 4mm diameter polyp,and is otherwise shiny and unremarkable. Representative sections of largest polyps submitted. Inking notation: proximal margin black, distal margin black, anterior circumferential margin blue, posterior circumferential margin green. BLOCK DESIGNATION: 1A - proximal margin. 1B - distal margin. 1C-1E - rectal tumor (submitted in full). 1F - largest rectal polyp bisected. 1G - four rectal polyps. 1H - seven whole nodes. 1I - six whole nodes. P9. 2. "Distal donut": A mucosal donut, 22x10mm, length 9mm. Staples removed. Longitudinal sections of mucosa submitted. P1. (CH) MICROSCOPIC DESCRIPTION: 1. The sections show invasive moderately differentiated adenocarcinoma arising in a tubulovillous adenoma with high grade dysplasia involving rectal mucosa. Tumor extends into the submucosa but does not appear to involve muscularis propria. No evidence of vascular, lymphatic or perineural invasion is seen. Of the five other polypoid lesions sampled, one is a sessile serrated adenoma and the remaining four are hyperplastic polyps. No evidence of metastatic tumor is seen in any of 10 lymph nodes. All resection margins are clear of tumor. 2. The section shows rectal mucosa and wall. A small hyperplastic polyp is noted within rectal mucosa. No evidence of invasive tumor is seen. DIAGNOSIS: 1. Rectum: Site - rectum. Type - moderately differentiated adenocarcinoma arising in tubulovillous adenoma with high grade dysplasia. Size - 20mm in maximum dimension. Local invasion - tumor extends through muscularis mucosae into submucosa; no evidence of involvement of muscularis propria seen. Lymphovascular invasion - absent. Perineural invasion - absent. Proximal, distal, radial - all clear of tumor. Lymph nodes - no evidence of metastatic tumor in any of 10 lymph nodes. Additional pathology - five sampled polypoid lesions - 1x sessile serrated adenoma; 4x hyperplastic polyp. AJCC (7th edition) Stage 1 (T1 N0 MX). *** Identification and sectioning of further lymph nodes pending Carnoy's treatment of perirectal fat. 2. Distal donut: Rectal mucosa with small hyperplastic polyp; no evidence of invasive tumor seen.


Gross pathological specimen showing the lesion in the rectum.

Case Discussion

This is an example of a T1 rectal cancer which has been completely excised with curative intent.

PlayAdd to Share

Case information

rID: 36921
Published: 19th May 2015
Last edited: 14th Aug 2019
Inclusion in quiz mode: Included

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.